Have fears of global shortage of high-grade collateral been exaggerated?

As the world braces for several more years of painful deleveraging from the pre-2007 credit excesses, one big fear has been that a shrinking pool of top-rated or AAA assets — due varioulsy to sovereign credit rating downgrades, deteriorating mortgage quality, Basel III banking regulations, central bank reserve accumulation and central clearing of OTC derivatives — has exaggerated the ongoing credit crunch. Along with interbank mistrust, the resulting shortage of high-quality collateral available to be pledged and re-pledged between banks and asset managers, it has been argued, meant the overall amount of credit being generating in the system has been shrinking, pushing up the cost and lowering the availability of borrowing in the real economy. Quantitative easing and bond buying by the world’s major central banks, some economists warned, was only exaggerating that shortage by removing the highest quality collateral from the banking system.